Polycarbonate resins exhibit excellent toughness, impact resistance, thermal stability, self extinguishability, dimensional stability and heat resistance and thus have been used in the production of electric and electronic products, automobile components, lenses, glass replacement materials, and the like. However, there can be various problems using polycarbonate resins in the production of products requiring transparency, such as significant deterioration in scratch resistance as compared to glass, and yellowing upon exposure to sunlight for a long period of time.
In contrast, unlike polycarbonate resins, poly(methyl methacrylate) (PMMA) resins can exhibit excellent weather resistance, transparency, flexural strength, flexural strain, adhesion, and the like, and thus have been used in adhesives, lighting materials, building materials, and the like. However, due to their low impact strength, PMMA cannot be used in products having less than a certain thickness in order to ensure sufficient impact strength.
It is expected that an alloy of such polycarbonate resins and PMMA resins could ensure both impact resistance and scratch resistance. However, in practice, due to poor compatibility and the large refractive index difference between these resins, the alloy is opaque and has poor appearance and quality, thereby exhibiting low impact resistance and scratch resistance.
Recently, in order to develop products having a luxurious appearance such as a highly glossy texture, resin compositions have been subjected to coating processes. However, these processes have problems in that they involve various steps, can have high defect rates, and can generate large amounts of volatile organic compounds, which can increase costs.
In order to solve these problems, non-painted materials have been developed. In order for a certain material to be used as a non-painted material, the material must have a highly glossy texture and provide scratch resistance upon coating. However, resins developed up to now are not satisfactory in terms of physical properties such as coloring property, impact resistance, heat resistance, scratch resistance, and the like.
The present inventors have developed a resin composition including a polycarbonate resin, a polycarbonate-polysiloxane copolymer, and a modified (meth)acrylic copolymer.
However, transparency and impact resistance of the composition can deteriorate when flame retardants are added for applications requiring flame retardancy such as home appliances and IT and OA devices. Further, when adding rubber components to improve impact resistance, the resin composition can exhibit decreased transparency and scratch resistance, and thus can fail to provide desired physical properties.
Therefore, there is a need to develop a resin composition which satisfies not only coloring property, impact resistance, heat resistance, and scratch resistance, but also transparency and flame retardancy.